In computing, iSCSI is an acronym for Internet Small Computer System Interface, an Internet Protocol (IP)-based storage networking standard for linking data storage facilities over a Storage Area Network (SAN). The iSCSI standard is defined and described by the IETF (Internet Engineering Task Force) standards body in Request for Comments (RFC) 3720, published April 2004. In iSCSI, Small Computer System Interface (SCSI) commands are carried over Internet Protocol (IP) networks, to facilitate data transfers and to manage storage over long distances [T10 is an American National Standards Institute (ANSI) body responsible for developing SCSI Standards that include SCSI Architecture Model (SAM), SCSI Primary Commands (SPC), SCSI Block Commands (SBC), Serial Attached SCSI (SAS), SES (SCSI Enclosure Standard), and SCC (SCSI Controller Commands), and further details of SCSI may be found in “http://www.t10.org/drafts.htm”]. Using the iSCSI protocol, data may be transmitted over networks, such as local area networks (LANs), wide area networks (WANs), or the Internet, to allow location-independent data storage and retrieval.
The iSCSI protocol allows clients (called initiators) to send SCSI commands to SCSI storage devices (called targets) on remote servers. Organizations are allowed to consolidate storage into data center storage arrays while providing hosts with the illusion of locally attached disks. iSCSI Initiators are the iSCSI devices that start an input/output (I/O process) and iSCSI targets are the iSCSI devices that respond to a request to perform an I/O process using SCSI standard commands.
In network data transmission operations in a computing environment, an initiator device transmits data or commands over the network to a target device. The initiator functions as an iSCSI client. An iSCSI initiator may be a software initiator or a hardware initiator. The hardware initiator may use hardware, typically in combination with software or firmware running on that hardware, to implement iSCSI.
A target device, such as, a server, storage controller or host computer, may include an iSCSI target controller or subsystem to access the SCSI commands stored in the payload of an iSCSI packet, and to perform the SCSI commands. The iSCSI target may comprise a dedicated network-connected hard disk storage device, a general-purpose computer, etc. In a data center or enterprise environment, an iSCSI target may reside in a large storage array. The storage array may provide distinct iSCSI targets for numerous clients.
Dynamic Host Configuration Protocol (DHCP) is a network protocol used to configure devices that are connected to a network so that the devices can communicate on the network using the Internet Protocol (IP). Further details of DHCP is defined and described by the IETF (Internet Engineering Task Force) standards body in RFC 2131 and 2132, both published March 1997. DHCP may be used in association with iSCSI for configuring devices